The invention relates to an improved brake test stand. Furthermore, the invention relates to an optimized method for testing a brake. The development times demanded by the market in the automotive sector are becoming increasingly shorter. At the same time the complexity of the assemblies of vehicles is steadily increasing. In the field of brake technology, therefore, test stands have been coming into use for many years with which new developments can be tested and improved before the presence of a complete vehicle. These test stands have the task to provide the most realistic conditions possible for the brake to be tested in order to make safe predictions on the future behavior of the brake in the vehicle.
An essential aspect in the simulation of braking operations on a test stand is the kinetic energy of the vehicle. This energy depends in reality on driving speed but also on vehicle weight and the driving situation, such as cornering or driving uphill or downhill.
Brake test stands are known in which the simulated kinetic energy of the vehicle is provided by rotating flywheel masses. The kinetic energy depends on the moment of inertia of the rotating flywheel mass. A disadvantage of such test stands is that different kinetic energies can only be simulated by changing the rotating mechanical flywheel mass. This requires mechanical modifications and is therefore not possible during a test run. Without modification of the flywheel mass, a change of the kinetic energy can be achieved only by changing the rotational speed. This contradicts in most cases the philosophy behind the test. For example, the difference in braking performance between a horizontal drive and a ride downhill (additional kinetic energy by the slope) would have to be realized at a known brake test stand via an increase in rotational speed when simulating driving. However, this increase in rotational speed will not take place in reality at the brake so that the simulated test provides no meaningful results.
Therefore, the object of the present invention is to improve the agreement of simulated braking tests with reality and thus to make the results obtained during the test more meaningful.
This object is achieved by a method for testing of at least one brake wherein the energy required for testing the brake or the torque required for testing the brake is provided by a drive motor, where at least prior to the testing of the brake a load generator is switched on and the energy required or the torque required, respectively, is built up or provided by a torque balance between the driving torque of a drive motor and a load torque of a load generator.